The present invention relates to a system for monitoring and observing data obtained by sensing from various kinds of facilities and a method of using the date, and in particular to a monitoring and observing portal site for building up, on a network of several computers, a means for producing a secondary process configuration of data obtained by monitoring and observing a certain facility, for an application used for a purpose different from that during the build-up of the system, and a method of using data monitored and observed.